Small and flat worlds: A complex network analysis of international trade in crude oil

• The spatial dynamics of crude trade is examined through small and flat worlds.
• Oil trade connectivity generally increased between 1988 and 2013.
• Complex networks and GIS show USA and China became top hubs in 2000 and 2013.
• Community structure identified four and five small worlds for 1990/2000 and 2013.
• Small worlds are connected across dispersed nodes and complemented by flat worlds.

Global competition for crude oil has increased in the past decade with the entry of industrializing nations such as China and India. Yet we still do not know much about the spatial structure of crude oil commodity trade and its evolution over time. In this paper, we apply complex network analysis to examine the geography of global crude oil flows and its evolution based on the United Nations commodity trade database from 1988 to 2013. Attention is given to the geo-visualization of the networks that trace the rise and decline of oil hubs. The results show that world crude oil is characterized by network characteristics that capture both small world and flat world properties.